Confusion about using Layout

I tried reading something about layout on http://www.extjs.com to understand the layout in ExtAsp.NET...but it is difficult.

I mean, the Row/Column layouts are very simple....but what about the others.

I am in the situation to use a Panel as a Table.....I mean inside a Table I can set a position for every element inside it....but with a Panel ( ext:Panel ) how could I put a button on the left-bottom position ?